Novel signal processing method for vital sign monitoring using FMCW radar

Ghaffar

et al. 2020

Sensors

Non-invasive remote health monitoring plays a vital role in epidemiological situations such as SARS outbreak (2003), MERS (2015) and the recently ongoing outbreak of COVID-19 because it is extremely risky to get close to the patient due to the spread of contagious infections. Non-invasive monitoring is also extremely necessary in situations where it is difficult to use complicated wired connections, such as ECG monitoring for infants, burn victims or during rescue missions when people are buried during building collapses/earthquakes. Due to the unique characteristics such as higher penetration capabilities, extremely precise ranging, low power requirement, low cost, simple hardware and robustness to multipath interferences, Impulse Radio Ultra Wideband (IR-UWB) technology is appropriate for non-invasive medical applications. IR-UWB sensors detect the macro as well as micro movement inside the human body due to its fine range resolution. The two vital signs, i.e., respiration rate and heart rate, can be measured by IR-UWB radar by measuring the change in the magnitude of signal due to displacement caused by human lungs, heart during respiration and heart beating. This paper reviews recent advances in IR-UWB radar sensor design for healthcare, such as vital signs measurements of a stationary human, vitals of a non-stationary human, vital signs of people in a vehicle, through the wall vitals measurement, neonate's health monitoring, fall detection, sleep monitoring and medical imaging. Although we have covered many topics related to health monitoring using IR-UWB, this paper is mainly focused on signal processing techniques for measurement of vital signs, i.e., respiration and heart rate monitoring.

Section: Vital Signs Detection Using Frequency Analysismentioning

confidence: 99%

An Overview of Signal Processing Techniques for Remote Health Monitoring Using Impulse Radio UWB Transceiver

Ghaffar

et al. 2020

Sensors

“…one band pass filter is employed in this paper. By employing the fifth filter, we can acquire = − S QW RW (19) where Q and R are filter coefficients.…”

Section: Snr Improvementmentioning

confidence: 99%

“…Impulse ultra-wideband (UWB) radar has been widely applied to track moving targets, through-wall imaging and son on due to its excellent time resolution and strong permeability [6][7][8][9][10][11][12][13]. However, extensive researches on life sign detection need to be made based on UWB radar [14][15][16][17][18][19][20][21][22]. In [14], a contactless human subject monitoring system is designed using a Doppler radar based on a four-tiered layer structure.…”

Section: Introductionmentioning

confidence: 99%

“…An omnidirectional detection system is designed and analyzed utilizing an antenna array technique [17]. The capability of the frequency modulated continuous wave (FMCW) radar for human respiratory signals detection is proven continuously and timely [19]. The performance of moving-target detection in UWB is validated based on the synthetic aperture radar (SAR) technique using the acquried single-channel SAR data [20].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Detection of Breathing Rates in Through-wall UWB Radar Utilizing JTFA

2019

KSII TIIS

Through-wall ultra-wide band (UWB) radar has been considered as one of the preferred and non-contact technologies for the targets detection owing to the better time resolution and stronger penetration. The high time resolution is a result of a larger of bandwidth of the employed UWB pulses from the radar system, which is a useful tool to separate multiple targets in complex environment. The article emphasised on human subject localization and detection. Human subject usually can be detected via extracting the weak respiratory signals of human subjects remotely. Meanwhile, the range between the detection object and radar is also acquired from the 2D range-frequency matrix. However, it is a challenging task to extract human respiratory signals owing to the low signal to clutter ratio. To improve the feasibility of human respiratory signals detection, a new method is developed via analysing the standard deviation based kurtosis of the collected pulses, which are modulated by human respiratory movements in slow time. The range between radar and the detection target is estimated using joint time-frequency analysis (JTFA) of the analysed characteristics, which provides a novel preliminary signature for life detection. The breathing rates are obtained using the proposed accumulation method in time and frequency domain, respectively. The proposed method is validated and proved numerically and experimentally.

Analog Integr Circ Sig Process

“…In contrast, CW and FMCW systems allow higher level of system integration and lower power operation. Note that the CW radar is not able to extract range resolution like UWB and FMCW radars [4]. Although FMCW radar allows measuring the distance of the target [5], the CW radar is superior to FMCW due to its higher measurement accuracy, less complex hardware architecture, and simpler signal processing techniques [6].…”

Section: Introductionmentioning

confidence: 99%

Heartbeat rate measurement using microwave systems: single-antenna, two-antennas, and modeling a moving person

El-Samad

Obeid

Zaharia

et al. 2018

This paper presents a microwave system for heartbeat rate measurement. This system is based on using a vector network analyzer and horn antennas. The system generates a continuous wave signal toward a person's chest then the reflected signal is analyzed. The phase difference between the emitted and the reflected signals contains information about the chest movement; hence, the heartbeat rate can be extracted. In this work, several scenarios for detecting the heart activity are considered. The first scenario aims to provide a comparative study for using single-antenna and two-antennas microwave systems. Several radiated powers are considered in this scenario. Simultaneously with the microwave system, a wireless electrocardiograph is used as reference in order to determine the accuracy of the system. Measurements are performed in both cases when breathing normally and when holding the breath. The second scenario aims to test the ability of detecting the heartbeat activity of a person while moving. Measurements are performed while the subject walks towards the radar. Modeling is used for this purpose. The operating frequency used is 20 GHz in both scenarios. Signals are processed using wavelet transform and results show the ability to extract the heartbeat rate even with the presence of body movement.